Gels are spread in wide fields including basic researches of their structures and physical properties and the like, application researches to food products, medical supplies, cosmetics and the like, and so on and attract attention, and the synthesis and development of novel gelling agents have been actively conducted (for example, see Patent Documents 1 to 3 below). However, there are involved problems such as difficulty in gelation under an acidic condition, requirement for multi-step synthetic process is and the like, and overcoming thereof is being desired.
On the other hand, carbon nanotubes are attracting attention as useful materials for nanotechnology. In particular, the carbon nanotubes are expected to be applied in wide range of fields such as transistors, electron emission electrodes, fuel cell electrodes, and chips for scanning microscope. When they are purified or prepared for applications as materials for the applications, it is necessary to prepare an easily handleable carbon nanotube solution or dispersed liquid. Thus, there is proposed a method for making hydrophobic carbon nanotubes soluble in a solvent, which includes adding a dispersing agent (generally an amphiphilic surfactant) to form a dispersion liquid (for example, see Non-Patent Document 1 below). Under the present circumstances, however, investigations for further improvements are still being carried out.
Under such a background, the present inventors found that a novel ionic organic oligomer having an electrolyte structure which is obtained by one step synthetic process by means of a polycondensation reaction between an aminopyridine and an acid halide having an active methylene group functions as a gelling agent against water and an acidic aqueous solution and further functions as a carbon nanotube dispersant and previously made a proposal (see Patent Document 4 below). However, in a synthesis method of the subject compound, a pyridyl site and an active methylene site each serving as a reaction site must exist in one molecule, so that syntheses of diverse ionic organic compounds are remarkably restricted.
As a result of synthetic expansion from the foregoing compound, we previously found that it is possible to synthesize ionic organic compounds by means of a copolymerization method and to utilize those ionic organic compounds as a hydrogelling agent and made an application (see Patent Document 5 below).
The present invention is concerned with synthesis of a new ionic organic compound in which the foregoing copolymerization method has been further developed and utilization of such an ionic organic compound as a hydrogelling agent and a methanol gelling agent and also as a carbon nanotube dispersant.
Citation List
Patent Document
Patent Document 1: JP-A-2003-327949
Patent Document 2: JP-A-2003-49154
Patent Document 3: JP-A-2003-55642
Patent Document 4: WO 2006/082768 A1
Patent Document 5: Japanese Patent Application No. 2007-324701
Non-Patent Document
Non-Patent Document 1: Science, Vol. 297, p. 593 (2002)